This application requests continued support for the NIEHS Center in Environmental Toxicology (UTMB-CET) at the University of Texas Medical Branch at Galveston. The mission of this Center is to integrate, coordinate and foster interactions and collaborations among a multidisciplinary group of established investigators pursuing research pertinent to the effects of environmental factors on human health. The investigators' proximity to sources of many significant environmental problems, such as ozone pollution, emissions of fine particulates, hazardous chemical releases, and hazardous waste sites makes UTMB a compelling site for an environmental health sciences Center. During the fifteen years of its existence, this Center has emerged as a national leader in elucidating cellular response mechanisms to environmental challenge, and in working with the community to enhance awareness of environmental health issues and elaborate prevention and intervention strategies. The overarching theme of the UTMB-CET is the role of oxidative stress in mediating the health effects of exposure to environmental factors. The Center supports multidisciplinary research, organized as Collaborative Research Teams (CRTs) integrating diverse approaches, to examine basic and translational research problems in environmental health. The CRT represents a transformative organizational structure that promotes and rewards collaborative team-based research. The UTMB-CET promotes mentored career development of young investigators, taking advantage of the CRT setting to enhance the training experience. Translational research activities are supported by five facilities within the Integrative Health Science Facility Core, providing the linkage between Center investigators, clinical resources, bioinformatic and biostatistical support services, and community resources. Center investigators are also aided by three established Facility Cores (Molecular Genetics, Biomolecular Resource Facility, and Synthetic Organic Chemistry) that provide advanced technologies, unique reagents, and specialized expertise for both basic and translational studies in a cost-effective manner. Scientific findings from the Center are communicated to the public through a vibrant Community Outreach and Engagement Core, with advice from a Stakeholder Advisory Board. The various activities of the UTMB-CET are coordinated by an Administrative Core, which receives input from an Internal Advisory Board, External Advisory Board, and the Executive Committee, and oversees a variety of programs including a Pilot Project Program, a seminars series, the Director's Fund, and a Discount Management Program. The UTMB-CET supports an outstanding portfolio of research projects in the field of environmental health sciences, with clear translational impact or potentia.